US President Barack Obama has asked Congress to quickly end the government's bulk collection of Americans' phone records. That could be asking a lot of lawmakers who do not often move quickly without a looming deadline.

Responding to public outrage over the National Security Agency programme, the Obama administration on Thursday unveiled a new programme that it said would address privacy concerns and preserve the government's ability to fight terrorism.

Under the proposal, Congress has three months to draft and pass a measure to end the bulk collection programme. The Obama administration has asked the courts to reauthorise that collection for another three months, while lawmakers consider an alternative. Under the current system, the government gets court approval every three months to collect all call records from certain phone companies daily.

The real looming deadline for action is June 1, 2015. That is when the section of a law that has been used to authorise the programme is set to expire.

Congress has been debating what to do about the once-classified programme since June last year, when former NSA systems analyst Edward Snowden revealed details about the massive surveillance operation.

Until now, many thought Congress would most likely let the phone records collection programme expire next year.

"I think that the administration was under the gun to come up with something that might satisfy those who want to see the end of the programme, such that they could avoid that result in 2015," said Kevin Bankston of the New America Foundation, a think tank.

Under the president's plan, the government would have to get a court order and ask phone companies to search their records for specific numbers that were believed to be associated with terrorists.

Phone companies would not hold onto the records for any longer than they are already required to under federal regulation, which is 18 months.

"I believe this approach will best ensure that we have the information we need to meet our intelligence needs while enhancing public confidence in the manner in which the information is collected and held," Obama said in a statement on Thursday. Obama has said that he never thought the programme was unconstitutional or ripe for abuse, but he was forced to respond to perceived privacy concerns.

Key lawmakers said they like some of Obama's proposal, but want more.

"I am glad that the president has come around," said senator Patrick Leahy, a Democrat.

This article appeared in the South China Morning Post print edition as Halt NSA data grab soon: Obama